Algorithmic Brush

I made a picture of a girl wearing a big hat on a misty day.

Girl wearing a hat

I made it using the mr doob harmony app, on the sketchy tool. The sketchy tool is an algorithmic brush, which is code which elaborates on lines you draw. I looked at the source code. Here it is:

stroke: function( mouseX, mouseY )
	{
		var i, dx, dy, d;

		this.points.push( [ mouseX, mouseY ] );

		this.context.lineWidth = BRUSH_SIZE;
		this.context.strokeStyle = "rgba(" + COLOR[0] + ", " + COLOR[1] + ", " + COLOR[2] + ", " + 0.05 * BRUSH_PRESSURE + ")";

		this.context.beginPath();
		this.context.moveTo(this.prevMouseX, this.prevMouseY);
		this.context.lineTo(mouseX, mouseY);
		this.context.stroke();

		for (i = 0; i < this.points.length; i++)
		{
			dx = this.points[i][0] - this.points[this.count][0];
			dy = this.points[i][1] - this.points[this.count][1];
			d = dx * dx + dy * dy;

			if (d < 4000 && Math.random() > (d / 2000))
			{
				this.context.beginPath();
				this.context.moveTo( this.points[this.count][0] + (dx * 0.3), this.points[this.count][1] + (dy * 0.3));
				this.context.lineTo( this.points[i][0] - (dx * 0.3), this.points[i][1] - (dy * 0.3));
				this.context.stroke();
			}
		}

		this.prevMouseX = mouseX;
		this.prevMouseY = mouseY;

		this.count ++;
	},

I can see that there are loops like I use in Scratch, and a random bit, too.